1. Field of the Invention
The method herein described is used to effectively seal pores in the material in the vicinity of recesses in porous materials (such as electrolytic cell anodes), which are used in corrosive environments and in which recesses connections to metal conductors are made, to prevent corrosion of the metallic conductors due to permeation of the porous material by corrosive components of the environment.
2. Description of the Prior Art
Special techniques are currently used to achieve an electrical contact to mercury cell anodes. These techniques often involve the use of a multiple connecting plug where a highly impregnated graphite plug is inserted between the graphite anode and the metal connector. This plug causes a high, power consuming, voltage drop and is complex to assemble.
Anodes which are used in cathodic protection, are currently impregnated with paraffin or linseed oil to protect the metal contact. However, the usual methods of impregnation do not give complete or uniform impregnation and problems of contact corrosion are still frequent.
Several U.S. patents relate to the general subject of impregnating carbon and/or graphite bodies but, none relate to impregnating recesses in graphite or other bodies in a manner and/or using an impregnating device, as taught in the present invention. Illustrative of such patents are the following: U.S. Pat. Nos. 1,861,415; 1,868,206; 1,909,800; 1,927,661, 2,207,734; 2,902,386; 3,167,447; 3,375,132; 3,529,997; 3,654,120.